A methodology for detecting the wound state sensing in terms of its colonization of pathogenic bacteria

A methodology for wound state sensing in terms of its colonization with pathogenic bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa has been developed. Here we report polydiacetylene (PDA) liposomes containing self-quenched carboxyfluorescein dye are only sensitive to toxins/enzymes secreted by Pathogenic bacteria but not by non-pathogenic species of Escherichia coli (DH5α). The basis of the detection assay is that at high concentration, carboxyfluorescein is non-fluorescent. Following breakdown of the bilayer of liposome containers by bacterial toxins, the dye becomes diluted and "switches on". The methodology can be easily adapted to evaluate the release of payloads from PDA liposomes in terms of fluorescence intensity and in addition to detect the potential interaction mechanism of biomimetic bilayer and pathogenic bacteria. •Self-quenched when encapsulated at high concentration, while fluorescence when diluted in solution•Easy quantification by measuring fluorescence intensity•Simple measurement procedure required (plate reading fluorimeter).